Samsung S5PC110 Manual page 1908

S5PC110_UM
6.3 BLOCK DIAGRAM OF SPDIF TRANSMITTER
APB Apb Interface
DMA Interface
Components in SPDI Transmitter:
• APB interface block: This block defines register banks to control the driving of SPDIFOUT module and data
buffers to store linear or non-linear PCM data.
• DMA interface block: This block requests DMA service to IODMA depending on the status of data buffer in
APB Interface block
• Clock Generator block: This block generates 128fs (sampling frequency) clock used in out_spdif block from
system audio clock (MCLK)
• Clock Multiplex block: system audio clock (MCLK) can be selected as internal MCLK or external MCLK.
• Audio_if_core block: This block acts as interface block between data buffer and out_spdif block. Finite-state
machine controls the flow of PCM data.
• spdif_tx block: This block inserts burst preamble and executes zero-stuffing in the nonlinear PCM stream.
Linear PCM data are bypassed by spdif_tx module.
• out_spdif block: This block generates SPDIF format. It inserts 4-bit preamble, 16- or 20- or 24-bit data, user-
data bit, validity bit, channel status bit and parity bit into the appropriate position of 32-bit word. It modulates
each bit to bi-phase format.
audio_if_core
I_MCLK_INT
I_MCLK_EXT
Figure 6-1 Block Diagram of SPDIFOUT
Spdif _tx
Clock
Clock
generator
Mux
6 SPDIF TRANSMITTER
out_spdif O_SPDIF_DATA
128 fs
6-2